import java.util.Scanner;

public class Text3 {
    public static void main(String[] args) {
        Scanner sca = new Scanner(System.in);
        int num = sca.nextInt();
        int falg = 1;
        for (int i = 2; i <num ; i++) {
            if(num%i==0){
                 falg = 0;
                 break;
            }
        }
        if(falg==1){
            System.out.println(num+"是素数");
        }else{
            System.out.println(num+"不是素数");
        }
    }
}
